Metamath Proof Explorer


Theorem xrhmph

Description: The extended reals are homeomorphic to the interval [ 0 , 1 ] . (Contributed by Mario Carneiro, 9-Sep-2015)

Ref Expression
Assertion xrhmph IIordTop

Proof

Step Hyp Ref Expression
1 neg1rr 1
2 1re 1
3 neg1lt0 1<0
4 0lt1 0<1
5 0re 0
6 1 5 2 lttri 1<00<11<1
7 3 4 6 mp2an 1<1
8 eqid TopOpenfld=TopOpenfld
9 eqid x01x1+1x-1=x01x1+1x-1
10 8 9 icchmeo 111<1x01x1+1x-1IIHomeoTopOpenfld𝑡11
11 1 2 7 10 mp3an x01x1+1x-1IIHomeoTopOpenfld𝑡11
12 hmphi x01x1+1x-1IIHomeoTopOpenfld𝑡11IITopOpenfld𝑡11
13 11 12 ax-mp IITopOpenfld𝑡11
14 eqid x01ifx=1+∞x1x=x01ifx=1+∞x1x
15 eqid y11if0yx01ifx=1+∞x1xyx01ifx=1+∞x1xy=y11if0yx01ifx=1+∞x1xyx01ifx=1+∞x1xy
16 14 15 8 xrhmeo y11if0yx01ifx=1+∞x1xyx01ifx=1+∞x1xyIsom<,<11*y11if0yx01ifx=1+∞x1xyx01ifx=1+∞x1xyTopOpenfld𝑡11HomeoordTop
17 16 simpri y11if0yx01ifx=1+∞x1xyx01ifx=1+∞x1xyTopOpenfld𝑡11HomeoordTop
18 hmphi y11if0yx01ifx=1+∞x1xyx01ifx=1+∞x1xyTopOpenfld𝑡11HomeoordTopTopOpenfld𝑡11ordTop
19 17 18 ax-mp TopOpenfld𝑡11ordTop
20 hmphtr IITopOpenfld𝑡11TopOpenfld𝑡11ordTopIIordTop
21 13 19 20 mp2an IIordTop